Question 1(a) [3 marks]

Discuss the main components of the Computer.

Answer:

Table: Main Components of Computer

Component	Function	Example
Input Unit	Receives data and instructions	Keyboard, Mouse
CPU	Processes data and controls operations	Intel i5, AMD Ryzen
Memory	Stores data temporarily/permanently	RAM, Hard Disk
Output Unit	Displays processed results	Monitor, Printer

Key Components:

Hardware: Physical parts like CPU, RAM, motherboard
Software: Programs and operating systems
Data: Information processed by computer

Mnemonic: "I Can Make Output" (Input-CPU-Memory-Output)

Question 1(b) [4 marks]

Explain the web browser and its type.

Answer:

A web browser is software that accesses and displays web pages from the internet.

Table: Types of Web Browsers

Browser Type	Features	Examples
Graphical	GUI interface, multimedia support	Chrome, Firefox
Text-based	Command line, fast loading	Lynx, Links
Mobile	Touch interface, optimized for phones	Safari Mobile, Chrome Mobile

Features:

Navigation: Forward, back, refresh buttons
Bookmarks: Save favorite websites
Tabs: Multiple pages in one window
Security: HTTPS support, popup blockers

Mnemonic: "Browse Safely Online" (Bookmarks-Security-Online)

Question 1(c) [7 marks]

Explain LAN, MAN and WAN with example.

Answer:

Table: Network Types Comparison

Network	Coverage	Speed	Example	Cost
LAN	Building/Campus	High (100Mbps-1Gbps)	Office network	Low
MAN	City/Metropolitan	Medium (10-100Mbps)	Cable TV network	Medium
WAN	Country/Global	Variable (1-100Mbps)	Internet	High

Detailed Explanation:

LAN (Local Area Network):

Coverage: Within building or small area
Technology: Ethernet, Wi-Fi
Example: Computer lab, home network

MAN (Metropolitan Area Network):

Coverage: Across city or metropolitan area
Technology: Fiber optic, microwave
Example: City-wide cable internet

WAN (Wide Area Network):

Coverage: Multiple cities/countries
Technology: Satellite, fiber optic
Example: Internet, bank ATM networks

Diagram:

graph LR
    A[LAN - Building] --> B[MAN - City]
    B --> C[WAN - Global]
    A --> D[Office Network]
    B --> E[City Cable TV]
    C --> F[Internet]

Mnemonic: "Local Metro World" (LAN-MAN-WAN)

Question 1(c OR) [7 marks]

Difference between DOS and Unix Operating system.

Answer:

Table: DOS vs Unix Comparison

Feature	DOS	Unix
Interface	Command Line (text-based)	Command Line + GUI
Multi-user	Single user	Multi-user support
Multitasking	Limited	Full multitasking
Security	Basic	Advanced security
File System	FAT16/FAT32	Various (ext3, ext4)
Cost	Commercial (Microsoft)	Free/Open source variants

Key Differences:

DOS (Disk Operating System):

Architecture: 16-bit, single-user
Memory: Limited to 640KB conventional
Commands: DIR, COPY, DEL
File naming: 8.3 format limitation

Unix:

Architecture: 32/64-bit, multi-user
Memory: Advanced memory management
Commands: ls, cp, rm, grep
File naming: Case-sensitive, long names

Examples:

DOS: MS-DOS, PC-DOS
Unix: Linux, Solaris, AIX

Mnemonic: "DOS Simple, Unix Powerful" (Single vs Multi-user)

Question 2(a) [3 marks]

List out features of operating system.

Answer:

Table: Operating System Features

Feature	Description
Process Management	Controls program execution
Memory Management	Allocates RAM efficiently
File Management	Organizes data storage
Device Management	Controls hardware devices

Core Features:

User Interface: GUI or command line
Security: User authentication, access control
Multitasking: Run multiple programs simultaneously
Resource Allocation: CPU, memory distribution

Mnemonic: "Please Manage Files Properly" (Process-Memory-File-Device)

Question 2(b) [4 marks]

Define half duplex and full duplex transmission modes.

Answer:

Table: Transmission Modes Comparison

Mode	Direction	Example	Efficiency
Half Duplex	Bidirectional (one at a time)	Walkie-talkie	Medium
Full Duplex	Bidirectional (simultaneous)	Telephone	High

Definitions:

Half Duplex:

Communication: Two-way but not simultaneous
Example: Radio communication, old Ethernet hubs
Limitation: Turn-taking required

Full Duplex:

Communication: Two-way simultaneous
Example: Modern Ethernet, telephone calls
Advantage: No waiting time

Diagram:

Half Duplex:
A -----> B  (A sends)
A <----- B  (B sends - A waits)

Full Duplex:
A <----> B  (Both send/receive simultaneously)

Mnemonic: "Half waits, Full flows" (Half=waiting, Full=simultaneous)

Question 2(c) [7 marks]

Difference between open source and proprietary software.

Answer:

Table: Open Source vs Proprietary Software

Aspect	Open Source	Proprietary
Source Code	Freely available	Hidden/Protected
Cost	Usually free	Paid licenses
Modification	Allowed	Restricted
Support	Community-based	Vendor support
Security	Transparent	Security through obscurity
Examples	Linux, Firefox, Apache	Windows, MS Office

Detailed Comparison:

Open Source Software:

Definition: Source code publicly available
Licensing: GPL, MIT, Apache licenses
Benefits: Cost-effective, customizable, transparent
Examples: LibreOffice, GIMP, MySQL

Proprietary Software:

Definition: Owned by individual/company
Licensing: End User License Agreement (EULA)
Benefits: Professional support, guaranteed updates
Examples: Adobe Photoshop, Oracle Database

Advantages & Disadvantages:

Open Source Pros: Free, flexible, community support Open Source Cons: Limited professional support

Proprietary Pros: Professional support, warranty Proprietary Cons: Expensive, vendor lock-in

Mnemonic: "Open = Free to See, Proprietary = Pay to Use"

Question 2(a OR) [3 marks]

Differentiate between RAM and ROM.

Answer:

Table: RAM vs ROM Comparison

Feature	RAM	ROM
Full Form	Random Access Memory	Read Only Memory
Volatility	Volatile (loses data)	Non-volatile (retains data)
Access	Read/Write	Read only
Speed	Very fast	Slower than RAM

Key Differences:

Purpose: RAM for temporary storage, ROM for permanent
Cost: RAM more expensive per GB
Usage: RAM for programs, ROM for firmware

Mnemonic: "RAM Runs, ROM Remembers" (temporary vs permanent)

Question 2(b OR) [4 marks]

Explain AND logic gate with Example.

Answer:

AND Gate Definition: Output is HIGH only when ALL inputs are HIGH.

Truth Table:

Input A	Input B	Output (A AND B)
0	0	0
0	1	0
1	0	0
1	1	1

Symbol:

    A ----\
           >---- Output
    B ----/

Example Applications:

Security System: Door opens only with key AND card
Car Starting: Engine starts with key AND foot on brake
Boolean Expression: Y = A · B or Y = A ∧ B

Real-life Example: Washing machine starts only when door is closed AND power button is pressed.

Mnemonic: "ALL inputs True = Output True"

Question 2(c OR) [7 marks]

Explain the Ethernet Cable Color code.

Answer:

Standard: TIA/EIA-568B Color Code

Table: Wire Color Sequence

Pin	Color	Function
1	White/Orange	Transmit+
2	Orange	Transmit-
3	White/Green	Receive+
4	Blue	Not used
5	White/Blue	Not used
6	Green	Receive-
7	White/Brown	Not used
8	Brown	Not used

Cable Types:

Straight-Through Cable (568B both ends):

Use: Computer to switch/hub
Color sequence: Same on both ends

Cross-Over Cable (568A one end, 568B other):

Use: Computer to computer direct
Pins swapped: 1↔3, 2↔6

Wiring Diagram:

RJ-45 Connector (568B):
Pin 1: White/Orange
Pin 2: Orange  
Pin 3: White/Green
Pin 4: Blue
Pin 5: White/Blue
Pin 6: Green
Pin 7: White/Brown
Pin 8: Brown

Preparation Steps:

Strip outer jacket (1 inch)
Arrange wires in color order
Cut wires evenly
Insert into RJ-45 connector
Crimp with crimping tool

Mnemonic: "White Orange, Orange, White Green, Blue, White Blue, Green, White Brown, Brown"

Question 3(a) [3 marks]

Compare wired and Wireless Communication.

Answer:

Table: Wired vs Wireless Communication

Aspect	Wired	Wireless
Medium	Cables (copper/fiber)	Radio waves/infrared
Speed	Higher (up to 100Gbps)	Lower (up to 1Gbps)
Security	More secure	Less secure
Mobility	Limited	High mobility
Cost	Higher installation	Lower installation
Interference	Minimal	Signal interference

Key Points:

Wired: Reliable, fast, secure but limited mobility
Wireless: Mobile, flexible but security concerns

Mnemonic: "Wires are Fast, Wireless is Free" (speed vs mobility)

Question 3(b) [4 marks]

Discuss the different types of computer systems.

Answer:

Table: Computer System Types

Type	Size	Processing Power	Example
Supercomputer	Room-sized	Extremely high	Weather forecasting
Mainframe	Large cabinet	Very high	Bank transactions
Minicomputer	Desk-sized	Medium	Small business
Microcomputer	Desktop/laptop	Low to medium	Personal use

Classifications:

By Size & Power:

Supercomputer: Scientific calculations, research
Mainframe: Large organizations, concurrent users
Personal Computer: Individual users, office work
Embedded Systems: Specific functions (washing machines)

By Purpose:

General Purpose: Versatile, multiple applications
Special Purpose: Dedicated tasks (ATM, gaming console)

Mnemonic: "Super Main Mini Micro" (decreasing size order)

Question 3(c) [7 marks]

Write short note on TDM, FDM, and OFDM.

Answer:

Multiplexing Techniques for Efficient Communication

Table: Multiplexing Comparison

Technique	Division Method	Application	Advantage
TDM	Time slots	Digital telephony	Simple implementation
FDM	Frequency bands	Radio/TV broadcasting	Simultaneous transmission
OFDM	Multiple carriers	Wi-Fi, 4G/5G	High data rates

Time Division Multiplexing (TDM):

Principle: Each user gets fixed time slot
Implementation: Sequential data transmission
Example: Digital telephone systems, GSM
Advantage: Efficient use of bandwidth

Frequency Division Multiplexing (FDM):

Principle: Each user gets unique frequency band
Implementation: Simultaneous transmission
Example: FM radio, cable TV
Advantage: No timing coordination needed

Orthogonal Frequency Division Multiplexing (OFDM):

Principle: Multiple orthogonal subcarriers
Implementation: Parallel data streams
Example: Wi-Fi (802.11), LTE, DSL
Advantage: High spectral efficiency, robust against interference

Diagram:

graph TD
    A[Data Stream] --> B[TDM - Time Slots]
    A --> C[FDM - Frequency Bands]
    A --> D[OFDM - Multiple Carriers]
    B --> E["T1|T2|T3|T4"]
    C --> F[F1 + F2 + F3 + F4]
    D --> G[Orthogonal Subcarriers]

Applications:

TDM: ISDN, T1/E1 lines
FDM: Analog TV, radio
OFDM: Modern wireless systems

Mnemonic: "Time Frequency Orthogonal" (TDM-FDM-OFDM)

Question 3(a OR) [3 marks]

Discuss FSK and PSK.

Answer:

Digital Modulation Techniques

Table: FSK vs PSK

Aspect	FSK	PSK
Parameter	Frequency	Phase
Complexity	Simple	Complex
Noise Immunity	Good	Excellent
Bandwidth	Higher	Lower

FSK (Frequency Shift Keying):

Principle: Different frequencies for 0 and 1
Implementation: f1 for '0', f2 for '1'
Example: Computer modems, RFID

PSK (Phase Shift Keying):

Principle: Phase changes represent data
Implementation: 0° for '0', 180° for '1'
Example: Wi-Fi, satellite communication

Mnemonic: "Frequency Shifts, Phase Shifts" (FSK-PSK)

Question 3(b OR) [4 marks]

Differentiate between Multitasking and Multi programming OS.

Answer:

Table: Multitasking vs Multiprogramming

Feature	Multitasking	Multiprogramming
User Interaction	Interactive	Batch processing
Response Time	Fast	Slower
CPU Sharing	Time slicing	Job switching
Example	Windows, Linux	Early mainframes

Multitasking:

Definition: Multiple tasks run seemingly simultaneously
Method: Time sharing with quick switching
User Experience: Interactive, responsive
Types: Preemptive, cooperative

Multiprogramming:

Definition: Multiple programs in memory
Method: CPU switches when I/O operations occur
User Experience: Batch job processing
Purpose: CPU utilization improvement

Mnemonic: "Tasks are Interactive, Programs are Batched"

Question 3(c OR) [7 marks]

Write short note on network topologies.

Answer:

Network Topology Types and Characteristics

Table: Topology Comparison

Topology	Structure	Advantages	Disadvantages	Cost
Bus	Linear	Simple, cost-effective	Single point failure	Low
Star	Central hub	Easy troubleshooting	Hub failure affects all	Medium
Ring	Circular	Equal access	Break affects network	Medium
Mesh	Interconnected	High reliability	Complex, expensive	High
Hybrid	Mixed	Flexible	Complex management	Variable

Detailed Descriptions:

Bus Topology:

Structure: Single backbone cable
Termination: Required at both ends
Example: Early Ethernet (10BASE2)
Failure Impact: Cable break stops entire network

Star Topology:

Structure: Central switch/hub with spokes
Scalability: Easy to add/remove nodes
Example: Modern Ethernet networks
Failure Impact: Only affected node fails

Ring Topology:

Structure: Nodes connected in circle
Data Flow: Unidirectional token passing
Example: Token Ring, FDDI
Failure Impact: Single break stops network

Mesh Topology:

Structure: Every node connected to every other
Types: Full mesh, partial mesh
Example: Internet backbone, military networks
Reliability: Multiple paths available

Hybrid Topology:

Structure: Combination of topologies
Example: Star-bus, star-ring
Flexibility: Best features of each type

Diagram:

graph TD
    A[Network Topologies] --> B[Bus]
    A --> C[Star]
    A --> D[Ring]
    A --> E[Mesh]
    A --> F[Hybrid]
    
    B --> G[Linear Connection]
    C --> H[Central Hub]
    D --> I[Circular Connection]
    E --> J[Full Interconnection]
    F --> K[Mixed Structure]

Selection Criteria:

Cost: Bus < Star < Ring < Mesh
Reliability: Bus < Ring < Star < Mesh
Scalability: Ring < Bus < Star < Mesh

Mnemonic: "Bus Star Ring Mesh Hybrid" (increasing complexity)

Question 4(a) [3 marks]

Explain Switch.

Answer:

Network Switch Definition and Functions

Table: Switch Characteristics

Feature	Description
Function	Connects devices in LAN
Layer	Data Link Layer (Layer 2)
Method	MAC address learning
Collision	Eliminates collisions

Key Features:

MAC Address Table: Learns and stores device addresses
Full Duplex: Simultaneous send/receive
Dedicated Bandwidth: Each port gets full bandwidth
VLAN Support: Virtual network segregation

Functions:

Frame Forwarding: Sends data to specific port
Address Learning: Builds MAC address table
Loop Prevention: Spanning Tree Protocol

Mnemonic: "Switch Learns MAC Addresses"

Question 4(b) [4 marks]

Define Cyberthreat with an example.

Answer:

Cyberthreat Definition: Malicious attempt to damage, disrupt, or gain unauthorized access to computer systems.

Table: Cyberthreat Types

Type	Method	Example	Impact
Malware	Malicious software	Virus, Trojan	Data corruption
Phishing	Fake emails/websites	Fake bank emails	Identity theft
Ransomware	Encrypt files	WannaCry attack	Financial loss
DDoS	Traffic overload	Server flooding	Service disruption

Example - Phishing Attack:

Method: Fake email from "bank"
Request: Login credentials
Result: Account compromise
Prevention: Verify sender authenticity

Common Indicators:

Suspicious emails: Unknown senders, urgent requests
Unusual system behavior: Slow performance, pop-ups
Unauthorized access: Changed passwords, new files

Mnemonic: "Cyber Criminals Create Chaos" (threats cause damage)

Question 4(c) [7 marks]

Compare TCP/IP and OSI networking models.

Answer:

Table: TCP/IP vs OSI Model Comparison

OSI Layer	OSI Function	TCP/IP Layer	TCP/IP Function
Application	User interface	Application	User services
Presentation	Data formatting	Application	(Combined)
Session	Session management	Application	(Combined)
Transport	Reliable delivery	Transport	End-to-end delivery
Network	Routing	Internet	IP addressing
Data Link	Frame handling	Network Access	Physical transmission
Physical	Electrical signals	Network Access	(Combined)

Key Differences:

OSI Model (7 layers):

Purpose: Theoretical reference model
Development: ISO standard
Layers: Clearly separated functions
Usage: Educational, troubleshooting

TCP/IP Model (4 layers):

Purpose: Practical implementation
Development: DARPA/Internet
Layers: Combined functionality
Usage: Internet, real networks

Advantages:

OSI Model:

Standardization: Universal reference
Troubleshooting: Layer-by-layer analysis
Education: Clear concept separation

TCP/IP Model:

Simplicity: Fewer layers
Practicality: Internet-proven
Flexibility: Protocol independence

Protocols Examples:

OSI: Conceptual framework
TCP/IP: HTTP, FTP, TCP, UDP, IP

Diagram:

graph TD
    A[OSI - 7 Layers] --> B[Application]
    A --> C[Presentation]  
    A --> D[Session]
    A --> E[Transport]
    A --> F[Network]
    A --> G[Data Link]
    A --> H[Physical]
    
    I[TCP/IP - 4 Layers] --> J[Application]
    I --> K[Transport]
    I --> L[Internet]
    I --> M[Network Access]

Mnemonic: "OSI is Perfect Theory, TCP/IP is Practical Reality"

Question 4(a OR) [3 marks]

Write main objectives of cyber security.

Answer:

Table: Cyber Security Objectives (CIA Triad)

Objective	Description	Example
Confidentiality	Protect data from unauthorized access	Encryption, passwords
Integrity	Ensure data accuracy and completeness	Digital signatures, checksums
Availability	Ensure system accessibility	Backup systems, redundancy

Additional Objectives:

Authentication: Verify user identity
Authorization: Control access rights
Non-repudiation: Prevent denial of actions

Mnemonic: "CIA protects data" (Confidentiality-Integrity-Availability)

Question 4(b OR) [4 marks]

List out different types of networking devices used in the networking.

Answer:

Table: Networking Devices

Device	Layer	Function	Example Use
Hub	Physical	Signal repeater	Legacy networks
Switch	Data Link	Frame forwarding	LAN connectivity
Router	Network	Packet routing	Internet connection
Bridge	Data Link	Network segmentation	LAN extension
Gateway	All layers	Protocol conversion	Network interconnection
Repeater	Physical	Signal amplification	Cable extension
Access Point	Data Link	Wireless connectivity	Wi-Fi networks
Firewall	Network+	Security filtering	Network protection

Functions:

Connectivity: Hub, switch, bridge
Routing: Router, gateway
Security: Firewall, proxy
Wireless: Access point, wireless router

Mnemonic: "Hubs Switch Routes Bridges Gateways"

Question 4(c OR) [7 marks]

Write different types of security attacks.

Answer:

Classification of Security Attacks

Table: Attack Types and Characteristics

Attack Type	Method	Target	Example	Prevention
Passive	Eavesdropping	Information	Traffic analysis	Encryption
Active	System modification	Integrity	Data alteration	Authentication
Physical	Hardware access	Equipment	Device theft	Physical security
Social Engineering	Human manipulation	Users	Phishing	User education

Detailed Attack Categories:

1. Network Attacks:

Man-in-the-Middle: Intercept communication
DDoS: Overwhelm server with traffic
Packet Sniffing: Capture network data
IP Spoofing: Fake source addresses

2. Application Attacks:

SQL Injection: Database manipulation
Cross-site Scripting (XSS): Web vulnerability
Buffer Overflow: Memory corruption
Zero-day Exploits: Unknown vulnerabilities

3. Malware Attacks:

Virus: Self-replicating code
Worm: Network-spreading malware
Trojan: Disguised malicious software
Ransomware: Data encryption for payment

4. Social Engineering:

Phishing: Fake emails/websites
Pretexting: False scenarios
Baiting: Malicious downloads
Tailgating: Physical access following

5. Cryptographic Attacks:

Brute Force: Try all combinations
Dictionary Attack: Common passwords
Rainbow Tables: Pre-computed hashes
Side-channel: Information leakage

Attack Vectors:

External: Internet-based attacks
Internal: Insider threats
Physical: Direct hardware access
Wireless: Wi-Fi vulnerabilities

Prevention Strategies:

Technical: Firewalls, antivirus, encryption
Administrative: Policies, procedures
Physical: Locks, surveillance
Education: User awareness training

Mnemonic: "Network Application Malware Social Crypto" (attack categories)

Question 5(a) [3 marks]

Calculate binary of (5AB.4) hexadecimal number.

Answer:

Hexadecimal to Binary Conversion

Method: Convert each hex digit to 4-bit binary

Table: Hex to Binary Conversion

Hex Digit	Binary	Hex Digit	Binary
5	0101	B	1011
A	1010	4	0100

Step-by-step Conversion:

5 → 0101
A → 1010
B → 1011
. → . (decimal point)
4 → 0100

Final Answer: (5AB.4)₁₆ = (010110101011.0100)₂

Simplified: (10110101011.01)₂

Mnemonic: "Each Hex = 4 Bits"

Question 5(b) [4 marks]

List out the main features of Digi-Locker, e-rupi.

Answer:

Table: Digital Platform Features

Platform	Purpose	Key Features	Benefits
Digi-Locker	Document storage	Cloud storage, digital certificates	Paperless verification
e-RUPI	Digital payment	QR/SMS voucher, pre-paid	Targeted welfare delivery

Digi-Locker Features:

Digital Wallet: Store documents in cloud
Authentication: Aadhaar-based verification
Integration: Government department access
Sharing: Secure document sharing

e-RUPI Features:

Prepaid Voucher: Purpose-specific payments
Contact-less: QR code/SMS based
Security: No personal/bank details shared
Usage: Healthcare, education, welfare schemes

Mnemonic: "Digi Stores, e-RUPI Pays" (storage vs payment)

Question 5(c) [7 marks]

Describe different generations of a computer system.

Answer:

Computer Generations Evolution

Table: Computer Generations Comparison

Generation	Period	Technology	Size	Speed	Examples
First	1940-1956	Vacuum Tubes	Room-sized	Slow	ENIAC, UNIVAC
Second	1956-1963	Transistors	Smaller	Faster	IBM 1401, CDC 1604
Third	1964-1971	Integrated Circuits	Desk-sized	Much faster	IBM 360, PDP-8
Fourth	1971-1980s	Microprocessors	Personal	Very fast	Intel 4004, Apple II
Fifth	1980s-Present	AI/Parallel Processing	Portable	Extremely fast	Modern PCs, smartphones

Detailed Description:

First Generation (1940-1956):

Technology: Vacuum tubes for logic/memory
Programming: Machine language, punch cards
Characteristics: Large, expensive, unreliable
Heat: Generated enormous heat
Examples: ENIAC (30 tons), UNIVAC I

Second Generation (1956-1963):

Technology: Transistors replaced vacuum tubes
Programming: Assembly language, FORTRAN, COBOL
Improvements: Smaller, faster, more reliable
Memory: Magnetic core memory
Examples: IBM 1401, Honeywell 400

Third Generation (1964-1971):

Technology: Integrated Circuits (ICs)
Programming: High-level languages
Features: Operating systems, multiprocessing
Size: Mini-computer emergence
Examples: IBM System/360, PDP-8

Fourth Generation (1971-1980s):

Technology: Microprocessors (CPU on chip)
Development: Personal computers born
Features: GUI, networking capabilities
Storage: Floppy disks, hard drives
Examples: Intel 8080, Apple II, IBM PC

Fifth Generation (1980s-Present):

Technology: AI, parallel processing, VLSI
Features: Internet, multimedia, mobile computing
Characteristics: User-friendly, portable, powerful
Current: Smartphones, tablets, cloud computing
Examples: Modern laptops, smartphones, supercomputers

Key Innovations by Generation:

1st: Electronic computing
2nd: Stored programs
3rd: Operating systems
4th: Personal computing
5th: Internet and AI

Diagram:

timeline
    title Computer Generations
    1940-1956 : First Generation
              : Vacuum Tubes
              : Room-sized
    1956-1963 : Second Generation
              : Transistors
              : Smaller size
    1964-1971 : Third Generation
              : Integrated Circuits
              : Minicomputers
    1971-1980s : Fourth Generation
               : Microprocessors
               : Personal Computers
    1980s-Present : Fifth Generation
                  : AI & Internet
                  : Mobile Computing

Mnemonic: "Vacuum Transistor IC Micro AI" (technology progression)

Question 5(a OR) [3 marks]

Write Difference between Data and Information with example.

Answer:

Table: Data vs Information

Aspect	Data	Information
Definition	Raw facts/figures	Processed data
Meaning	No context	Has context
Example	85, 92, 78	Average score: 85%
Purpose	Input for processing	Output for decision-making

Examples:

Data: Student marks (85, 92, 78, 88)
Information: Class average is 85.75%

Characteristics:

Data: Unorganized, raw, needs processing
Information: Organized, meaningful, useful for decisions

Mnemonic: "Data is Raw, Information is Refined"

Question 5(b OR) [4 marks]

Compare analog modulation and digital modulation.

Answer:

Table: Analog vs Digital Modulation

Feature	Analog Modulation	Digital Modulation
Signal Type	Continuous	Discrete (0s and 1s)
Noise Immunity	Poor	Excellent
Bandwidth	Lower	Higher
Quality	Degrades with distance	Maintains quality
Examples	AM, FM radio	FSK, PSK, QAM

Analog Modulation:

Types: AM (Amplitude), FM (Frequency), PM (Phase)
Applications: Radio broadcasting, analog TV
Advantages: Simple, lower bandwidth
Disadvantages: Noise susceptible, quality loss

Digital Modulation:

Types: ASK, FSK, PSK, QAM
Applications: Wi-Fi, cellular, satellite
Advantages: Noise resistant, error correction
Disadvantages: Complex, higher bandwidth

Mnemonic: "Analog is Simple, Digital is Smart"

Question 5(c OR) [7 marks]

Discuss the range of IP addresses in IPv4

Answer:

IPv4 Address Range and Classification

Table: IPv4 Address Classes

Class	Range	Default Subnet	Networks	Hosts per Network	Usage
A	1.0.0.0 - 126.0.0.0	/8 (255.0.0.0)	126	16,777,214	Large organizations
B	128.0.0.0 - 191.255.0.0	/16 (255.255.0.0)	16,384	65,534	Medium organizations
C	192.0.0.0 - 223.255.255.0	/24 (255.255.255.0)	2,097,152	254	Small organizations
D	224.0.0.0 - 239.255.255.255	N/A	N/A	N/A	Multicast
E	240.0.0.0 - 255.255.255.255	N/A	N/A	N/A	Reserved/Experimental

Special Address Ranges:

Private IP Ranges (RFC 1918):

Class A: 10.0.0.0 - 10.255.255.255 (/8)
Class B: 172.16.0.0 - 172.31.255.255 (/12)
Class C: 192.168.0.0 - 192.168.255.255 (/16)

Reserved Addresses:

Loopback: 127.0.0.0 - 127.255.255.255
Link-local: 169.254.0.0 - 169.254.255.255
Broadcast: x.x.x.255 (last address in subnet)
Network: x.x.x.0 (first address in subnet)

Address Structure:

Total IPv4 space: 4,294,967,296 addresses (2³²)
Format: 32-bit address in dotted decimal
Example: 192.168.1.100

Subnet Calculation Example:

Network: 192.168.1.0/24
Subnet Mask: 255.255.255.0
Host Range: 192.168.1.1 - 192.168.1.254
Broadcast: 192.168.1.255

CIDR Notation:

/8: 255.0.0.0 (Class A default)
/16: 255.255.0.0 (Class B default)
/24: 255.255.255.0 (Class C default)
/30: 255.255.255.252 (Point-to-point links)

IPv4 Exhaustion:

Problem: Limited address space
Solution: IPv6 (128-bit addresses)
Temporary fixes: NAT, CIDR, private addressing

Diagram:

graph TD
    A[IPv4 Address Space] --> B[Class A: 1-126]
    A --> C[Class B: 128-191]  
    A --> D[Class C: 192-223]
    A --> E[Class D: 224-239 Multicast]
    A --> F[Class E: 240-255 Reserved]
    
    B --> G[Large Networks]
    C --> H[Medium Networks]
    D --> I[Small Networks]

Applications:

Public IPs: Internet routing
Private IPs: Internal networks
Multicast: One-to-many communication
Loopback: Local testing

Mnemonic: "A Big Company Delivered Everything" (Classes A-B-C-D-E)